Determinants of regioselectivity of heterostructures in cation exchange reactions.

A cation exchange (CE) reaction offers a remarkable opportunity to create versatile metal sulfide nanocrystals (NCs) with arbitrary complexity in composition, structure, and functionality. The concept of regioselectivity has been discovered and developed to build the target heterostructures through CE reactions, yet a general principle of regioselectivity remains unclear. In this work, we establish connections between experimental results and theoretical insights to elucidate the determinants of regioselectivity using designed aliovalent CE reactions on a two-dimensional template.

Study on the discoloration phenomenon caused by iron ion oxidation in Boston ivy pads and its effect on adhesion force.

Boston ivy has received much attention from researchers owing to its exceptional climbing abilities. However, many aspects of their adhesion behavior remain unresolved. Our research has discovered a phenomenon of oxidation and discoloration in Boston ivy pads, which leads to a significant decrease in adhesion force.

Four-step continuous-flow total synthesis of (-)-debromoflustramine B using a chiral heterogeneous Pd NP catalyst.

Various prenylated indoline alkaloids with diverse biological activities, including (-)-debromoflustramine B with significant butyrylcholinesterase inhibitory activity, could be synthesized by dearomative prenylation reactions of tryptophan derivatives. However, previously reported dearomative prenylations were limited to batch reactions at the milligram scale, requiring multistep reactions and complex post-processing to obtain the desired natural products. The more efficient synthesis of alkaloids remains challenging, as does the recovery of expensive catalysts.

Highly enantioselective synthesis of both enantiomers of tetrahydroquinoxaline derivatives Ir-catalyzed asymmetric hydrogenation.

A novel Ir-catalyzed asymmetric hydrogenation protocol for the synthesis of chiral tetrahydroquinoxaline (THQ) derivatives has been developed. By simply adjusting the reaction solvent, both enantiomers of mono-substituted chiral THQs could be selectively obtained in high yields with excellent enantioselectivities (toluene/dioxane: up to 93% yield and 98% ee (); EtOH: up to 83% yield and 93% ee ()). For 2,3-disubstituted chiral THQs, the -hydrogenation products were obtained with up to 95% yield, 20 : 1 dr, and 94% ee.

Data-driven discovery of active phosphine ligand space for cross-coupling reactions.

The design of highly active catalysts is a main theme in organic chemistry, but it still relies heavily on expert experience. Herein, powered by machine-learning global structure exploration, we forge a Metal-Phosphine Catalyst Database (MPCD) with a meticulously designed ligand replacement energy metric, a key descriptor to describe the metal-ligand interactions. It pushes the rational design of organometallic catalysts to a quantitative era, where a ±10 kJ mol window of relative ligand binding strength, a so-called active ligand space (ALS), is identified for highly effective catalyst screening.

Artificial intelligence driven molecule adsorption prediction (AIMAP) applied to chirality recognition of amino acid adsorption on metals.

Predicting the adsorption structure of molecules has long been a challenging topic given the coupled complexity of surface binding sites and molecule flexibility. Here, we develop AIMAP, an Artificial Intelligence Driven Molecule Adsorption Prediction tool, to achieve the general-purpose end-to-end prediction of molecule adsorption structures. AIMAP features efficient exploration of the global potential energy surface of the adsorption system based on global neural network (G-NN) potential, by rapidly screening qualified adsorption patterns and fine searching using stochastic surface walking (SSW) global optimization.

Leveraging phenazine and dihydrophenazine redox dynamics in conjugated microporous polymers for high-efficiency overall photosynthesis of hydrogen peroxide.

Harnessing solar energy for hydrogen peroxide (HO) production from water and oxygen is crucial for sustainable solar fuel generation. Conjugated microporous polymers (CMPs), with their vast structural versatility and extended π-conjugation, are promising photocatalysts for solar-driven HO generation, though enhancing their efficiency is challenging. Inspired by the crucial role of phenazine derives in biological redox cycling and electron transfer processes, the redox-active phenazine moiety is rationally integrated into a CMP framework (TPE-PNZ).

Unveiling the mechanism of tuning elemental distribution in high entropy alloys and its effect on thermal stability.

The issue of elemental distribution such as chemical short range order (SRO) in high entropy alloys (HEAs) has garnered increased attention in both experimental and theoretical realms. A comprehensive and urgently required elucidation of this atomic-level phenomenon is the focus of this study. In this work, we systematically analyzed atomic-level information, involving atomic volume, charge transfer, local chemical ordering and atomic stress in 3d HEAs.

From cubane-assembled Mn-oxo clusters to monodispersed manganese oxide colloidal nanocrystals.

The assemblies of [MO] (M = metal) cubanes represent a fascinating class of materials for a variety of application fields. Although such a structural characteristic is relatively common in small molecules and in extended bulk solids, high nuclearity clusters composed of multiple [MO] units as their backbones are rare. In this work, we report two new Mn-oxo clusters, Mn Mn O(OOCMe)(OMe)(py) ([Mn-Ac]) and Mn Mn O(OOCCMe)(OMe)(MeOH)(py) ([Mn-Piv]), whose core structures are assemblies of either 6- or 7-cubanes in different packing patterns, which have been unambiguously revealed by single crystal X-ray diffraction technique.

Weakly-Supervised Segmentation-Based Quantitative Characterization of Pulmonary Cavity Lesions in CT Scans.

Objective: Pulmonary cavity lesion is one of the commonly seen lesions in lung caused by a variety of malignant and non-malignant diseases. Diagnosis of a cavity lesion is commonly based on accurate recognition of the typical morphological characteristics. A deep learning-based model to automatically detect, segment, and quantify the region of cavity lesion on CT scans has potential in clinical diagnosis, monitoring, and treatment efficacy assessment.

Copper-catalyzed asymmetric allylic substitution of racemic/ substrates.

The synthesis of enantiomerically pure compounds is a pivotal subject in the field of chemistry, with enantioselective catalysis currently standing as the primary approach for delivering specific enantiomers. Among these strategies, Cu-catalyzed asymmetric allylic substitution (AAS) is significant and irreplaceable, especially when it comes to the use of non-stabilized nucleophiles (p > 25). Although Cu-catalyzed AAS of prochiral substrates has also been widely developed, methodologies involving racemic/ substrates are highly desirable, as the substrates undergo dynamic processes to give single enantiomer products.

High-purity CN quantum dots for enhancing fluorescence detection of metal ions.

A new type of two-dimensional layered material, namely CN, has been fabricated by polymerization and recommended to have great potential in various applications such as the development of electronic devices or photo-detectors, due to its enhanced conductivity, electronegativity, and unique optical properties. Actually, most of the present research on CN is limited in the scope of theoretical calculation, while experimental research is blocked by inefficient synthesis with low purity and homogeneity. Here, we report an optimized efficient synthesis method of high-purity CN QDs in aqueous solution by polymerization of DAP with combined centrifugation and filtration of products, with the synthesis yield up to 33.

From π-conjugated macrocycles to heterocycloarenes based on benzo[2,1-:3,4-']dithiophene (BDTh): size- and geometry-dependent host-guest properties.

π-Conjugated macrocycles have been highly attractive due to their challenging synthesis, fascinating aesthetic structure and unique physical and chemical properties. Although some progress has been made in synthesis, the study of π-macrocycles with different structural characteristics and supramolecular interactions still faces major challenges. In this paper, two new single-bond linked macrocycles (MS-4T/MS-6T) were reported, and the corresponding vinyl-bridged heterocycloarenes (MF-4T/MF-6T) were synthesized by the periphery fusion strategy.

Discovery and engineering of ribosomally synthesized and post-translationally modified peptide (RiPP) natural products.

Ribosomally synthesized and post-translationally modified peptides (RiPPs) represent a diverse superfamily of natural products with immense potential for drug development. This review provides a concise overview of the recent advances in the discovery of RiPP natural products, focusing on rational strategies such as bioactivity guided screening, enzyme or precursor-based genome mining, and biosynthetic engineering. The challenges associated with activating silent biosynthetic gene clusters and the development of elaborate catalytic systems are also discussed.

Influence of annealing pretreatment in different atmospheres on crystallization quality and UV photosensitivity of gallium oxide films.

Due to their high wavelength selectivity and strong anti-interference capability, solar-blind UV photodetectors hold broad and important application prospects in fields like flame detection, missile warnings, and secure communication. Research on solar-blind UV detectors for amorphous GaO is still in its early stages. The presence of intrinsic defects related to oxygen vacancies significantly affects the photodetection performance of amorphous GaO materials.

Optoelectronic synapses based on a triple cation perovskite and Al/MoO interface for neuromorphic information processing.

Optoelectronic synaptic transistors are attractive for applications in next-generation brain-like computation systems, especially for their visible-light operation and in-sensor computing capabilities. However, from a material perspective, it is difficult to build a device that meets expectations in terms of both its functions and power consumption, prompting the call for greater innovation in materials and device construction. In this study, we innovatively combined a novel perovskite carrier supply layer with an Al/MoO interface carrier regulatory layer to fabricate optoelectronic synaptic devices, namely Al/MoO/CsFAMA/ITO transistors.

α-Lipoic acid chemistry: the past 70 years.

α-Lipoic acid (ALA) is a naturally occurring sulfur-containing fatty acid with high antioxidant activity. It is also used to treat diabetes, nerve pain, weight loss, heart disease, and primary mitochondrial disorders. Moreover, numerous therapeutic agents have been studied for managing other clinical conditions, including for anticancer, anti-HIV, anti-inflammatory, and anti-AD treatments.

Evoking C production from electrochemical CO reduction by the steric confinement effect of ordered porous CuO.

Selective conversion of carbon dioxide (CO) to multi-carbon products (CO-to-C) at high current densities is in essential demand for the practical application of the resultant valuable products, yet it remains challenging to conduct due to the lack of efficient electrocatalysts. Herein, three-dimensional ordered porous cuprous oxide cuboctahedra (3DOP CuO-CO) were designed and synthesized by a molecular fence-assisted hard templating approach. Capitalizing on the merits of interconnected and uniformly distributed pore channels, 3DOP CuO-CO exhibited outstanding electrochemical CO-to-C conversion, achieving faradaic efficiency and partial current density for C products of up to 81.

An optimal Fe-C coordination ensemble for hydrocarbon chain growth: a full Fischer-Tropsch synthesis mechanism from machine learning.

Fischer-Tropsch synthesis (FTS, CO + H → long-chain hydrocarbons) because of its great significance in industry has attracted huge attention since its discovery. For Fe-based catalysts, after decades of efforts, even the product distribution remains poorly understood due to the lack of information on the active site and the chain growth mechanism. Herein powered by a newly developed machine-learning-based transition state (ML-TS) exploration method to treat properly reaction-induced surface reconstruction, we are able to resolve where and how long-chain hydrocarbons grow on complex formed Fe-carbide (FeC) surfaces from thousands of pathway candidates.

N/O Co-doped hierarchical nanoporous biochar derived from waste polypropylene nonwoven for high-performance supercapacitors.

How to efficiently treat municipal solid waste (MSW) has become one of the critical solutions in response to the call for "carbon neutrality". Here, the waste polypropylene nonwoven fabric of waste diapers was converted into hierarchical nanoporous biochar (HPBC) through pre-carbonization and activation processes as an ideal precursor for supercapacitors (SCs) with excellent performance. The prepared HPBC-750-4 with an ultrahigh specific surface area (3838.

Highly enantioselective synthesis of both tetrahydroquinoxalines and dihydroquinoxalinones Rh-thiourea catalyzed asymmetric hydrogenation.

Chiral tetrahydroquinoxalines and dihydroquinoxalinones represent the core structure of many bioactive molecules. Herein, a simple and efficient Rh-thiourea-catalyzed asymmetric hydrogenation for enantiopure tetrahydroquinoxalines and dihydroquinoxalinones was developed under 1 MPa H pressure at room temperature. The reaction was magnified to the gram scale furnishing the desired products with undamaged yield and enantioselectivity.

The luminescence mechanism of ligand-induced interface states in silicon quantum dots.

Over decades of research on photoluminescence (PL) of silicon quantum dots (Si-QDs), extensive exploratory experiments have been conducted to find ways to improve the photoluminescence quantum yield. However, the complete physical picture of Si-QD luminescence is not yet clear and needs to be studied in depth. In this work, which considers the quantum size effect and surface effect, the optical properties of Si-QDs with different sizes and surface terminated ligands were calculated based on first principles calculations.